Is there any way to turn off the 5G band on the Linksys extender as there is only 2.4G band on my at&t router?




Yes, you can do that, you have to login the extender settings and then disable the 5G band.

Yes, there is. You have to log in to the extender's settings and then disable the 5G band.
there is another alternative as well:- while you are setting up your Extender, during the 5G band setup, just select "I don't need the second network" and then hit next.